Asbestos: mining exposure, health effects and policy implications

Our plain-English summary of Asbestos: mining exposure, health effects and policy implications, by K. Luus (McGill Journal of Medicine, 2007).

The study

• Author: K. Luus
• Journal: McGill Journal of Medicine
• Published: 2007;10(2):121-6
• Cited by: 6 articles, as counted by NIH iCite
• Read it: PubMed · Free full text

Abstract

The purpose of this paper is to review research in the health effects and risks associated with exposure to asbestos and then to use this scientific evidence to analyze the implications of Canada's current policy on the use, manufacturing and export of asbestos. The review begins with a brief historical introduction to asbestos, and then moves on to look at the risks associated with asbestos exposure. Epidemiological and in vitro studies are then analyzed to determine the health risks of asbestos, with a specific focus on the different effects of serpentine and amphibole asbestos fibres. The paper then concludes with an analysis of Canadian policy in light of established scientific evidence and with a discussion of the possible implications of a gap between scientific knowledge and public policy.

In plain English

This paper was a review of published research on the health effects of asbestos, followed by a critique of Canadian asbestos policy. It did not report new data. The author focused on exposure in asbestos mining and on differences between serpentine chrysotile and amphibole types, including crocidolite, and also discussed tremolite. Drawing on cited studies, the author argued that amphibole fibres persist much longer in the lungs than chrysotile, that asbestosis is contracted mainly through amphibole fibres, and that mesothelioma rates are much greater after amphibole exposure. The review described a cited study of 7,307 residents of Libby, Montana, who had been exposed to amphibole asbestos. In that group, 6.7% had autoimmune diseases, compared with 1% in an unexposed Missoula population. The author noted that whether asbestos causes autoimmune disease was still incompletely explored. The author also argued that longer chrysotile fibres may be more genotoxic. The author concluded that Canadian policies were not based on scientific evidence. The author called for Canada to stop exporting asbestos to EU countries that have banned it, while stating that chrysotile is less potent than other forms.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Narrative literature review with a policy critique; no new data were collected
• Who was studied: Published research on asbestos health effects, with a focus on occupational risks of asbestos mining, plus Canadian asbestos legislation and export policy
• Exposure: Inhaled asbestos: serpentine (chrysotile) compared with amphibole forms (amosite, crocidolite, anthophyllite); tremolite in contaminated talc and vermiculite and in Quebec chrysotile
• Main results:
  • Citing other work, the review reported that chrysotile fibres have a half-life in the lung of 0.3-11 days, while amphibole fibres have a half-life of 500 days to infinity. The author concluded that amphiboles are more irritative.
  • Based on nine epidemiological studies reviewed by Hessel et al. and on other cited work, the author concluded that asbestosis is contracted primarily through amphibole fibres.
  • Citing other studies, the review stated that malignant mesothelioma rates are much greater in populations exposed to amphibole fibres.
  • The review described a cited study of 7,307 Libby, Montana residents exposed to amphibole asbestos from a vermiculite mine. In that group, 6.7% were diagnosed with autoimmune diseases, compared with 1% in an unexposed Missoula population.
  • The author argued that genotoxicity is related to fibre length, so longer chrysotile fibres are more genotoxic than short amphibole fibres. The author noted that this runs counter to other reviews.
  • The author judged the Canadian Hazardous Products Act ban on products made entirely of asbestos fibre too narrow to affect community exposure.
• The authors' conclusion: The author concluded that Canadian asbestos policies were not based on scientific evidence of asbestos health effects. The author stated that chrysotile is less potent than other forms, but called for Canada to stop exporting asbestos to EU countries that have banned it.
• Limitations the authors state:
  • The author noted that, despite the statistically significant Libby findings, the causal link between asbestos exposure and autoimmune diseases was still incompletely explored.

Topics

Medical terms in this study, explained in our Lexicon: Asbestos Exposure, Serpentine Group, Amphibole Asbestos.

Related studies

• Asbestos: scientific developments and implications for public policy — B.T. Mossman, J. Bignon, et al. (1990)
• Determining satisfaction with access and financial aspects of care for persons exposed to Libby amphibole asbestos: rural and national environmental policy implications — C.A. Winters, W. Hill, et al. (2011)
• Exposures estimates of the Wittenoom mining workforce and town residents - Implications associated with risk estimation for persons exposed to asbestiform riebeckite — A.J. Rogers (2018)
• Asbestos as a public health risk: disease and policy — H. Weill, J.M. Hughes (1986)
• Public health advocacy strategies to influence policy agendas: lessons from a narrative review of success in trade policy — B. Townsend, B.F. Tenni, et al. (2023)
• Rural public health policy models to address an evolving environmental asbestos disaster — S.W. Kuntz, C.A. Winters, et al. (2009)

Browse return to medical research.